In primary aldosteronism (PA), aldosterone secretion is relatively independent of the renin-angiotensin system, but can be regulated by several other stimuli. The objective of this study was to evaluate aldosterone response to several stimuli in a series of patients with PA secondary either to bilateral adrenal hyperplasia (BAH) or unilateral aldosterone-producing adenoma (APA). The aberrant regulation of aldosterone was systematically explored using an in vivo protocol that included the following stimulation tests performed over 3 days under dexamethasone suppression: upright posture, mixed meal, adrenocorticotropin (ACTH) 1-24, gonadotropin-releasing hormone (GnRH), vasopressin, and serotonin R4 agonist. Positive response was defined as >50% renin or ACTH-independent increase in plasma aldosterone/cortisol concentration following the various stimulation tests. Renin-independent aldosterone secretion increased in response to several aberrant stimuli (upright posture, GnRH) in up to 83% of patients with APA or BAH in whom ACTH 1-24 and HT4R agonists also produced aldosterone oversecretion in all patients. The mean significant aberrant responses per patient was similar in BAH (4.6) and in APA (4.0). Aldosterone secretion in PA is relatively autonomous from the renin-angiotensin system, but is highly regulated by several other stimuli, which contributes to the large variability of aldosterone levels in PA patients.
Authors: Matthieu St-Jean, Isabelle Bourdeau, Marc Martin, André Lacroix
Keywords: G-protein coupled receptor, aberrant regulation, aldosterone, cortisol cosecretion, primary aldosteronism
DOI Number: 10.1210/clinem/dgaa703 Publication Year: 2020
To search for other research papers by topic, keyword, author, or year, please go to our Publications page.